New to me 97 RN SJ - What's been done to it?

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#1
So I recently picked up a new to me 1997 Roundnose Superjet. The thing runs great but I had a pretty bad (or good depending how you look at it) submarine and managed to hit the bottom of the lake. Snapped a couple of my motor mounts.

Already ordered new ones from Jet Maniac; in the process of starting to disassemble the ski I see some weird stuff.

Can anyone tell me what mods have likely been done to this based on some of the pics? I've highlighted what seems to be off in red in each pic.

First off: the carb support brackets don't reach the head - is this not the stock carb or are these for something else?
IMG_7497.jpg IMG_7498.jpg


Second: On the carb at the front of the ski a bolt is clamped in a tube to cap off what looks like the carb vent/return line?
IMG_7495.jpg

Third: the yellow hose I recently replaced, it goes from what looks like a carb return to a return on the top of the fuel tank - there was a crusty old hose on here when I bought the ski and it was leaking fuel, so I replaced with a new line. No idea if this is where it's supposed to go.
IMG_7496.jpg



The more that I look at the carbs I can see that the low-speed and high-speed needles are different on each carb, only maybe by 1/8 of a turn. I'll be pulling the motor out in the next couple days - what else should I look for/be doing with it out?


THANKS!
-p2im0
 
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#2
Also, which position on the stock fuel valve is on/off/reserve? My valve goes from the 9 o'clock position, to 6 o'clock, and 3 o'clock - not sure which is which.
 

Mike W

Infidel
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#4
The previous owner probably had different carbs that required the second pulse line. Just cap it, not a big deal.

The head looks like an older 61x that doesn’t have the mounts for that style carb brace. Not a big deal either.

The yellow fuel line is just the return line from the carbs. Just tuck it away along the hull with all the other fuel lines to tidy it up a bit.
 

smoofers

Rockin' the SQUARE!!!!
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#5
The crank cases on that motor are not original to that ski. Somebody swapped in 760 cases that have the dual pulse line fittings. The pulse line is what transmits positive and negative pressure to run the fuel pump on your carb. Stock 38mm carbs only need one pulse line, so the second one is capped off.
 
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#6
The crank cases on that motor are not original to that ski. Somebody swapped in 760 cases that have the dual pulse line fittings. The pulse line is what transmits positive and negative pressure to run the fuel pump on your carb. Stock 38mm carbs only need one pulse line, so the second one is capped off.
Thanks for the info guys.

@smoofers the head does say it’s a 61X, what ski would be 760 case be off of? Anything I need to know if it is a 760 case?

Thanks!
 
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#8
Okay - I could use some more help from the gurus.

First, what's this rubber thing used for on the midshaft housing?
InkedIMG_7229_LI.jpg

Second, I was reading up on what it takes to do dual cooling - when I looked at my pump I noticed there's a separate intake on the left side of the pump that's capped off with some fuel line and a bolt - what kind of pump is this? Stock doesn't have that, right? (Where do I look for identifying marks? Under ride-plate?)

InkedIMG_7222_LI.jpg
InkedIMG_7234_LI.jpg IMG_7220.jpg IMG_7224.jpg IMG_7225.jpg

Third, I'm assuming my front pump bolts shouldn't have the washers "loosely" moving around on them like this quick vid I uploaded to YouTube. Both sides do this - I've been riding the ski like this after buying it - what to look for for damage?

Last, what do you use between ride-plate and hull? Just a clear silicone? I intend to pull off the plate to get a better look at those bolts and how loose they actually are.

In summary
  • Rubber thing on midshaft housing?
  • What kind of pump with extra coolant pickup on left?
  • Wiggly front pump bolts, WTFmate?
  • Silicone between ride-plate and hull?

Just got my parts from JetManiac - about to put in some couch mounts, bilge, and some other goodies while motors out.

THANKS!
 
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#9
The rubber piece on your mid shaft is for the coupler cover. It slides on there n bolts to the case in 2 spots. Bolts should be tight, no wiggles. Just clear silicone around the bolt hole location. Helps with water going through the threads
 
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#13
It’s all aluminum. Coloring on the photo is weird because of the shop light I used to light it.

Stock pump doesn’t have two inlets does it? Or is it stock pump (6-vane) and the inlet is on the reduction nozzle?
 
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#15
In summary
  • Rubber thing on midshaft housing?
  • What kind of pump with extra coolant pickup on left?
  • Wiggly front pump bolts, WTFmate?
  • Silicone between ride-plate and hull?

Just got my parts from JetManiac - about to put in some couch mounts, bilge, and some other goodies while motors out.

THANKS!
What pump... It looks like a stock 144mm pump that has been tapped for dual cooling, actually I`m sure as that is how my pump looks. If you wanted to use the second tap you would hook it to the through hull tube that is currently being used for the venturi bilge. Install a Rule/Tsunami bilge pump or two, ditch the siphon bilge and re use that line to feed the engine in addition to the current line. On your current build however its not necessary, once you get a pipe and head you may want to consider it.

Wiggly bolts... Welcome to second hand jet ski ownership. Mine was so poorly put together I ended up pulling all parts and reinstalling properly on the entire ski. Check the midshaft housing rubber and seals for cracks and tears if you pull the pump/motor. It has seals and rubber on the back as well. The bearing rides in a large rubber buffer to account for driveline movement, once they start coming apart they dont last long and if is put in a constant bind they have a short lifespan regardless of condition.

Silicone between the ride plate and hull.... Using silicone on all mating surfaces for ride plate and intake grate is pretty common. It helps make sure you dont suck water between the plate and the intake grate and create cavitation. I used a bead of regular silicone and ran my finger over it to wipe up excess. Recommended.

Additionally... Do yourself a favor and drill your steering nozzle for quick steer, single best mod I did to my superjet, it came alive in the steering after I did it. Simply drill a new hole inboard where the steering nozzle hooks to the cable. There is a lot of flat surface on the arm and you can move it in even farther than I did, picture below.
20180704_145548_HDR[1].jpg
 
Last edited:

smoofers

Rockin' the SQUARE!!!!
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#16
What pump... It looks like a stock 144mm pump that has been tapped for dual cooling, actually I`m sure as that is how my pump looks. If you wanted to use the second tap you would hook it to the through hull tube that is currently being used for the venturi bilge. Install a Rule/Tsunami bilge pump or two, ditch the siphon bilge and re use that line to feed the engine in addition to the current line. On your current build however its not necessary, once you get a pipe and head you may want to consider it.

Wiggly bolts... Welcome to second hand jet ski ownership. Mine was so poorly put together I ended up pulling all parts and reinstalling properly on the entire ski. Check the midshaft housing rubber and seals for cracks and tears if you pull the pump/motor. It has seals and rubber on the back as well. The bearing rides in a large rubber buffer to account for driveline movement, once they start coming apart they dont last long and if is put in a constant bind they have a short lifespan regardless of condition.

Silicone between the ride plate and hull.... Using silicone on all mating surfaces for ride plate and intake grate is pretty common. It helps make sure you dont suck water between the plate and the intake grate and create cavitation. I used a bead of regular silicone and ran my finger over it to wipe up excess. Recommended.

Additionally... Do yourself a favor and drill your steering nozzle for quick steer, single best mod I did to my superjet, it came alive in the steering after I did it. Simply drill a new hole inboard where the steering nozzle hooks to the cable. There is a lot of flat surface on the arm and you can move it in even farther than I did, picture below.
View attachment 358281
Great post. Spot on on all points. I also second the quicksteer mod, the greatest free mod you can do to improve steering response.
 
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#18
Awesome thanks for all the info Req!!



Yeah oddly enough this is the first I’ve seen of this, even on a couple of the “must have first Superjet” mods threads I’ve read through!
I think it's such a common mod for people in the community they forget to mention it. I felt the same way as I put 10 hours of tray time in before I even realized I could do it.
 
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#19
So I had this blue ventilation hose that runs up the handle pole, it was run under the stock tank and just sitting on the bottom of the hull, where is that supposed to go?

 
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